Art of producing metallic iridium.



, UNITED STATES PATENT orrron- HERSOHEL (J. PARKER, OF NEW YORK, N. Y.,ASSIGNOR TO. PARKER-CLARK ELECTRIC COMPANY, OF JERSEY CITY, NEWJERSEY,'A CORPORATION OF NEW JERSEY.

Specification of Letters Patent.

Eatented. Nov. 21, 1905.

Application filed June 21, 1906. Serial No. 266,222.

To all whom it may concern.-

Be it known that I, HERSCHEL C. PARKER, of New York, county of Kings,and State of New York, have invented a new and useful Improvement in theArt of Producing Metallic Iridium,'of which the following is a full,

Isq

clear, and exact description.

My invention relates to improvements in the art. of producing iridium ina metallic state, and especially to improvements which enable theiridium to be deposited in the form of a metallic film upon certainsurfaces, and particularly on the surface of refractory and transparentmaterialssuch, for instance, as uartz. In a general way my process issimilar to that described in myapplication for Letters Patent of theUnited States for a process of making incandescent electric lamps,Serial No. 254,588, filed April 8, 1905.

It is well known that most attempts to pro-- duce iridium result .inleaving it in the form of a powder or incoherent mass. I have found,however, that b taking iridiumpowder, especially in the form ofiridiumammonium chlorid, and mixing this with am monium chlorid, so asto form an excess of the ammonia compound, and then subjecting themixture to high heat while it 1s. in contact with a refractory substancethe iridium is deposited in the form of a metal on the said refractorysubstance, and the other constituents of the mixture, being volatile,

pass off. In carrying out this process it is obvious that I can producethe film in mirror form on a tube or sheet and that the iridium can'beremoved from the tube or sheet for other purposes. It willbe seen, then,that I am able, first, to make a splendid metallic mirror, and, second,that I can produce iridium in a metallic state capable of being used forwire, metal sheets, or any desired form.

With these ends in view my invention consists of an improvement in theart of producing iridium in a metallic state, which improvement will behereinafter described and claimed.

I take, first, iridium-ammonium chlorid, the formula of which isprobably With this I mix an equal volume of ammonium chlorid, or themixture may be in the ratio of three parts to two of theiridium-ammonium chlorid, or it can-be varied, more or less, accordingto the effect desired and the amount of heat to be used. The hardnessand thickness of-the film to be deposited is governed somewhat b cess ofammonium chlbrid in the mixture. If the film is to be produced on atube, I pack the above mixture snugly in the-tube to be coated and thenthe flame of a small blastlamp is directed upon the tube, the flamebeing directed progressively along the tube, and the heat causes thevolatile parts of the mixture lic form is deposited on the inner wall ofthe tube. I have used the heat of the lamp with good effect; but it willof course be understood that the heat may be applied in other wayswithout affecting the invention, and it is also likely that othervolatile substanceslike ammonium carbonate, for instance might besubstituted for the ammonium chlorid; but the essential thing is tohavea volatile substance which has a reducing action.

In my ex eriments I have had the mixture substantia y as given in theformula; but I do not wish to confine my invention to these proportionsor tothe precise mixture given.

I the iridium is to be produced on a plate,

the amount of exthe mixture is as stated above, and the plate the art ofproducing metallic iridium, which consists in mixing the iridiumcompound in powder form with a reducing agent, placing the powder on arefractory substance and then heating the substance so as to drive offthe volatile matter and leave the metallic iridium on the refractorymaterial. I

2. The improvement in the art of producing metallic iridium whichconsists in mix.- ing compounds of iridium chlorin and ammonium with anammonium compound and 5 to be driven off, while the iridium in metalthenheating the mixture whereby the volatile matter is driven ofi' and theiridium deposited in a coherent metallic form.

3. The improvement in the art of p'l'odu'c ing metallic iridium whichconsists in mixing compounds of iridium chlorin and ammonium with anexcess of ammonium chlorid and then subjecting the mixture to heatwhereby the volatile matter is driven ofi' and coherent metallic iridiumis deposited.

4. The improvement in the art of producing metallic iridium whichconsists in subjecting an iridium compound to a'high heat in thepresence of an ammonium compound whereby the volatile matter is drivenoff and coherent metallic iridium in sheet form is deposited.

5. The herein-described improvement in the art of producing metalliciridium which consists in mingling compounds of iridium ammonium andchlorin With an ammonium compound and then subjecting the mass tosufficient heat to drive off the volatile matter thereby depositingcoherent metallic iridium. 6. The herein-described improvement in theart of producing metallic iridium which consists in mingling iridiumammonium chlorid with a volatile reducing agent, confining the mass in arefractory substance, and then heating said refractory substance, thusdriving of? the volatile matter and depositing the iridium in metallicform;

HERSCHEL C. PARKER. Witnesses:

WARREN B. HUTCHINSON, J. C. BANTA.

